Napkin Gladwell is a journalist and bestselling author of books people read on airplanes. He occasionally provides Deadspin with excerpts of his upcoming essays.

On a recent Tuesday, a tennis player named Venus Williams, 29 years old, bent over as she began the coiling motion of her service. Venus was playing in the Australian Open, which is a tennis tournament, against Lucie Safarova, a tennis player, who is 22 years old and from Brno, which is in the Czech Republic. Venus, who is from Compton, Calif., was wearing a short dress, which was yellow, and when she stooped to gather herself, the dress rode up on her haunches, exposing what looked very much like her ass, which was awesome.

But what did we really see? Were we looking at her bare ass? Or were we looking at flesh-colored lycra? Was it a puzzle? Or was it a mystery? Is Venus a Revealer or a Concealer? And what can we learn about the market for credit derivatives by staring at length at Venus Williams's ass?

In order to determine something you thought was fairly straightforward, you really have to take into account a series of things that aren't so straightforward. During the summer of 1943, Nazi propaganda broadcasts boasted that the German military had developed a devastating "super weapon." Immediately, the Allied intelligence services went to work. Spies confirmed that the Germans had built a secret weapons factory. Aerial photographs taken over northern France showed a strange new concrete installation pointed in the direction of England. The Allies were worried. Bombing missions were sent to try to disrupt the mysterious operation, and plans were drawn up to deal with the prospect of devastating new attacks on English cities. Nobody was sure, though, whether the weapon was real. There seemed to be weapons factories there, but it wasn't evident what was happening inside them. And there was a launching pad in northern France, but it might have been just a decoy, designed to distract the Allies from bombing real targets. The German secret weapon was a puzzle, and the Allies didn't have enough information to solve it.

Were the Nazis Concealers or were they Revealers? Were the Allies looking at lycra, in other words, or were they looking at bare ass? These are questions that Vikram Anand, as investment analyst with Credit Suisse, knows all too well. Anand, in a classic study of the freight derivatives market on the Baltic Exchange ...